Abstract: A time-base generator with a self-compensating control loop. The time-base generator is suitable for use in level measurement and time-of-flight ranging systems. The time-base generator includes a pulse generator stage, a delay stage, a control loop and a references voltage module. The pulse generator generates a transmit pulse train and a receive or sampling pulse train with a delayed timing relationship. The control loop functions with the delay stage to maintain the desired delay between the first pulse train and the second pulse train. According to another aspect, the time-base generator includes a calibration module. The calibration module generates calibration pulses which are used by the controller in the level measurement system to calibrate operation.

Abstract: A pulse offset calibration method for a pulse-echo level measurement system. The pulse-echo level measurement system includes a transducer for transmitting calibration acoustic pulses and receiving echo pulses. A receiver converts the echo pulses into corresponding pulse profile signals having a leading edge. A static delay interval is defined on the leading edge corresponding to the time interval between the reception of the echo pulse and the response by the receiver. A dynamic delay interval is defined on the leading edge corresponding to the time response characteristics of the transducer and the receiver. The static delay interval and the dynamic delay interval are summed to determine the offset time interval for the echo pulse. The offset time interval is subtracted from the measurements to provide the true duration for the time of flight.

Abstract: A microwave-based level measurement system having a planar microwave antenna configuration. According to another aspect, the microwave-based level measurement devices are field interchangeable with ultrasonic based level measurement devices.

Abstract: A time-base generator with a self-compensating control loop. The time-base generator is suitable for use in level measurement and time-of-flight ranging systems. The time-base generator includes a pulse generator stage, a delay stage, a control loop and a references voltage module. The pulse generator generates a transmit pulse train and a receive or sampling pulse train with a delayed timing relationship. The control loop functions with the delay stage to maintain the desired delay between the first pulse train and the second pulse train. According to another aspect, the time-base generator includes a calibration module. The calibration module generates calibration pulses which are used by the controller in the level measurement system to calibrate operation.

Abstract: A calibration module and methods for a time-of-flight ranging system. The calibration module may be built into the circuitry of the time-of-flight ranging system and allows various operating parameters to be measured and evaluated. The calibration modes include amplitude calibration, frequency calibration, and time delay calibration. The calibration mode also includes an electronic noise measurement mode. The calibration modes may be initiated on power-up or reset, or in response to user input or time-based trigger.

Abstract: A pulse offset calibration method for a pulse-echo level measurement system. The pulse-echo level measurement system includes a transducer for transmitting calibration acoustic pulses and receiving echo pulses. A receiver converts the echo pulses into corresponding pulse profile signals having a leading edge. A static delay interval is defined on the leading edge corresponding to the time interval between the reception of the echo pulse and the response by the receiver. A dynamic delay interval is defined on the leading edge corresponding to the time response characteristics of the transducer and the receiver. The static delay interval and the dynamic delay interval are summed to determine the offset time interval for the echo pulse. The offset time interval is subtracted from the measurements to provide the true duration for the time of flight.

Abstract: A calibration module and methods for a time-of-flight ranging system. The calibration module may be built into the circuitry of the time-of-flight ranging system and allows various operating parameters to be measured and evaluated. The calibration modes include amplitude calibration, frequency calibration, and time delay calibration. The calibration mode also includes an electronic noise measurement mode. The calibration modes may be initiated on power-up or reset, or in response to user input or time-based trigger.

Abstract: A power saving system and method for the analog-to-digital converter stage in a time of flight ranging system. A receiving echo signal having an envelope is converted into a digital form suitable for further processing by sampling the received echo signal envelope at precise intervals to obtain amplitude measurement points. An interpolation function is applied between each pair of adjacent amplitude measurement points. The application of the interpolation function provides a closer approximation of the shape of the received echo signal envelope without the need to use higher sampling rates which means slower analog-to-digital converters may be utilized resulting in power and cost savings.

Abstract: A method of measuring the position of a target feature in a pulse-echo ranging system including transmitting at least one pulse of high frequency energy from a transducer towards the target feature, receiving energy reflected back from the direction of the target feature to the transducer to provide at least one return signal, repeatedly sampling the amplitude of the return signal(s) at intervals to form a digital database relating signal amplitude to elapsed time, and searching the database for at least one target zone in which a greater than background rate of fall of the return signal amplitude is sustained.